Sorghum is a domesticated plant well known to man. It has been hybridized since early Egyptian times and is highly diversified in its varieties. As used herein, the terms “sorghum” and “milo” may be used interchangeably. In the United States, varieties of sorghum have few uses other than for animal feed or as a less expensive feed grain substitute for corn or wheat. In other parts of the world, particularly Africa and Asia, sorghum is used for flour and human food.
There are hundreds of varieties of sorghum with each variety having slightly different characteristics. One area in which sorghum varieties differ from one another is in their antioxidant content. Sorghum typically contains the antioxidant chemical compounds classified as tocopherols, anthocyanins, and polyphenols. Each variety of sorghum may contain a specific combination of one or more of these antioxidants in different amounts within the various components or structures of the plant. Thus, for example, the seed hull of a specific sorghum variety may contain different antioxidants at amounts that are different from those in the endogerm of the same seed.
In certain applications, sorghum may be extruded into a matrix for various purposes. In one such application, the extruded matrix may be used as a construction component, such as an insulation material. Not all sorghum is created equal for extrusion purposes, however. Some varieties may extrude very well, while others may not extrude at all or only with great difficulty, depending on the desired characteristics of the final extruded product. Heretofore, to determine whether a particular variety of sorghum would yield an extrusion product having desirable characteristics, it was necessary to test the sorghum in an actual extrusion process. This is time consuming and inefficient, however, and requires utilization of expensive extrusion equipment that could otherwise be used in more productive applications.